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1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
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104 Posts
Discussion Starter #1
Ok i am planning to do it soon but lacking knowledge..
Since this job concerns brakes and i am being a safety engineer i would like to be sure about what i am doing before i start...

Did my homework and searched the forum but still need a bir more.
My car is a 1988 (built late 1987) 560SEC with ASR option this is the first year which i believe they offered ASR on 126 chasis.

Factory manual method suggests bleeding the brakes and after that bleeding the ASR pump while engine is running. Thats ok but my problem is, beside the 4 nipples on brake calipers and one ont he ASR pump (port marked "SP") i have two more bleeding nipples in the system: one on the ABS unit and one on a junction in between....

How will this system be bleed properly? what should be the sequence?
And idea / experience will be greatly appriciated (sorry for the long post)
 

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Premium Member
2012 CL550 4MATIC Coupe
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9,992 Posts
When I had ASR in my car, I purged it normally. I started with the wheel farthest from the res. and work your way around. RR irst, the LR, RF then LF. Then do it again.
 

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1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
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104 Posts
Discussion Starter #3 (Edited)
Thank you Mclare,

That part of the job is clear and i ve done it several times on cars with just ABS. what i need to know is the bleeding sequence in the engine bay. Namely what should be the order between the bleeding ports of the ASR pump, the junction and the ABS pump.. And there exist a label on the ABS pump saying "CAUTION FOLLOW SPECIAL INSTRUCTIONS WHILE BLEEDING" or something like that...
 

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1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
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104 Posts
Discussion Starter #5
I think i need the instructions mentioned on the label..
126 Factorl manual only coveres the ASR pump with SP port... not he other 2
 

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Premium Member
2012 CL550 4MATIC Coupe
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9,992 Posts
Umut,

I don't have that kind of ASR pump. My two look completely different and there is no label on mine. I have almost all of the parts to my ASR system sitting in a box F/S since I pulled mine and don't need them anymore.

Sorry I can't be of help.
 

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1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
Joined
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104 Posts
Discussion Starter #7
Umut,

I don't have that kind of ASR pump. My two look completely different and there is no label on mine. I have almost all of the parts to my ASR system sitting in a box F/S since I pulled mine and don't need them anymore.

Sorry I can't be of help.
Thanks McLare,

That will be my action to get rid of the ASR completely as soon as i locate a throttle linkage of a non ASR car. Mine keeps cutting the acceleration for no apparent reason during cruising at normal speed and throttle response is history after that.. it becomes very hard to depress the pedal.. i think the actuator binds or jams...

anyway I agree with you on Mercedes should have waited W140 to release first ASR....


I will take my chance and change the brake fluid as i normally do.

Regards
 

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Premium Member
2012 CL550 4MATIC Coupe
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9,992 Posts
Yeah, I think you'll be okay.

BTW - Taking out the ASR is no small feat and merely changing the throttle linkage will not suffice, that's what someone did to mine. Once the ASR fails, it takes the ABS system too. And the Cruise is also linked to it. When you remove it, you have to take out the entire brake system, C/C system, and half the dash to swap everything.

Read my thread HERE, where I detailed how I did it.
 

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2012 CL550 4MATIC Coupe
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9,992 Posts
Thanks McLare,
It's not McLare, it's mclare as in Michael Clare, my name.

Mine keeps cutting the acceleration for no apparent reason during cruising at normal speed and throttle response is history after that.. it becomes very hard to depress the pedal.. i think the actuator binds or jams...
The reason it keeps cutting out and it will not go beyond a certain point is because it has failed, and it is in the "Limp Home Mode" whereby the computer limits the power output to 2/3's of rated power to not let you skid.

If you swap linkages, that will defeat that, but your C/C won't work. This is the same problem I had.

In a Non-ASR car the C/C is subordinate to the throttle pedal (Hence, the drivers command) so that if the Cruise is on and you gas it, you take over.

Just the opposite with ASR. With ASR the throttle pedal (Again, Drivers command) is subordinate to the Cruise Control Actuator. Meaning that if the car thinks you are causing a skid or slide, it overrides you and say "NoNo" and lifts the throttle for you, giving you no say. Later models a override switch was installed, but not ours. And one CANNOT be put in. Two years ago I talked to the guy that made the aftermarket override circuit, and he say 99% sure nope. And that if he could make one, it would be in the 3000-4000 dollar price range. I told him pass, and Bondavi and I started researching and planning on how to remove it.

I founf a nice '88 coupe in the JY and ElRojo and I spent 4 days pulling everything out of it. ABS pump, all brake lines, harnesses, computer, Cruise computer, actuator, differential, sensors, everything. Then I spent about a month putting it all back into my car. At the time I was doing a motor swap, so everything was out of my engine bay and it was relatively easy. I say that now, but you can ask Mapearso and Bondavi how many times they had to talk me down off the tower!

Looking back it was not that hard. It's harder for me as I've had two heart attacks, so I have to go a little easier and can't work long days in the sun anymore. But with the engine out, it's not that bad. I was fanatical and replaced all of the brake lines, but you don't really need to. You can make due with a single going to the rear, but you will have to use a bender and make the spot for the tee. ASR cars have one line per wheel, non-ASR cars have a single brake line to both rear wheels. Also the diff is different too. It has dual speed sensors, you only need the one.
 

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Registered
1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
Joined
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104 Posts
Discussion Starter #10
Yeah, I think you'll be okay.

BTW - Taking out the ASR is no small feat and merely changing the throttle linkage will not suffice, that's what someone did to mine. Once the ASR fails, it takes the ABS system too. And the Cruise is also linked to it. When you remove it, you have to take out the entire brake system, C/C system, and half the dash to swap everything.

Read my thread HERE, where I detailed how I did it.
First my apologies for the spelling.
It is mclare from now on.. :)

We started with brake fluid change and ended up talking about removing entire brake circuit. I can live without ASR and cruise control but removing the entire brake system may be out of my weekend wrenching capabilities...

I will definitely read that tread in my spare times it seems like a "must read" for all SEC owners. Thank you for documenting your work.
 

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Registered
1990 W124 200E (daily driver), 1988 C126 560SEC (weekend fun)
Joined
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104 Posts
Discussion Starter #11
It's not McLare, it's mclare as in Michael Clare, my name.



The reason it keeps cutting out and it will not go beyond a certain point is because it has failed, and it is in the "Limp Home Mode" whereby the computer limits the power output to 2/3's of rated power to not let you skid.

If you swap linkages, that will defeat that, but your C/C won't work. This is the same problem I had.

In a Non-ASR car the C/C is subordinate to the throttle pedal (Hence, the drivers command) so that if the Cruise is on and you gas it, you take over.

Just the opposite with ASR. With ASR the throttle pedal (Again, Drivers command) is subordinate to the Cruise Control Actuator. Meaning that if the car thinks you are causing a skid or slide, it overrides you and say "NoNo" and lifts the throttle for you, giving you no say. Later models a override switch was installed, but not ours. And one CANNOT be put in. Two years ago I talked to the guy that made the aftermarket override circuit, and he say 99% sure nope. And that if he could make one, it would be in the 3000-4000 dollar price range. I told him pass, and Bondavi and I started researching and planning on how to remove it.

I founf a nice '88 coupe in the JY and ElRojo and I spent 4 days pulling everything out of it. ABS pump, all brake lines, harnesses, computer, Cruise computer, actuator, differential, sensors, everything. Then I spent about a month putting it all back into my car. At the time I was doing a motor swap, so everything was out of my engine bay and it was relatively easy. I say that now, but you can ask Mapearso and Bondavi how many times they had to talk me down off the tower!

Looking back it was not that hard. It's harder for me as I've had two heart attacks, so I have to go a little easier and can't work long days in the sun anymore. But with the engine out, it's not that bad. I was fanatical and replaced all of the brake lines, but you don't really need to. You can make due with a single going to the rear, but you will have to use a bender and make the spot for the tee. ASR cars have one line per wheel, non-ASR cars have a single brake line to both rear wheels. Also the diff is different too. It has dual speed sensors, you only need the one.
Thank you for the detailed explenation of how things go on in the ASR. Picture is much clear now...
From the very first day of my ownership this car didnt seem to have 220 kw.
(Yes i have tri y s and 10:1 compression)
This explains my lack of power: Car actually has the potential but that stupid ASR doesnt allow me to use all...

After a few seconds of driving i get both ABS and ASR lights in the cluster on so i assume i have at least one faulty speed sensor.

Can you tell me if both ABS and ASR systems use the same imput signal from each wheel or do they have seperate sensors for each system?

I dont think i can find a SEC in the JYard here they are so rare...
My plan is to use the linkage from a Gen II V8 (probably sedan) and try to learn living without ASR and C/C.. I think can live without them but driving a 220 Kw car like a 300SD is out of question.. :))
 
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